Open-pore or open cavity molding processes for manufacturing molded rubber or plastic products are known. In a typical prior art open cavity molding process, a single piece mold having a concave portion formed therein is filled with a liquid rubber or plastic material, and the mold is inserted in an oven to cure the material. After curing, the finished product is removed from the mold. These open cavity molding processes of the prior art are relatively inexpensive and are particularly useful for manufacturing substantially flat thin products including floor mats, such as those typically used in automobiles and other vehicles. In typical open cavity molding processes, a single color of material is used to make single color products.
Products manufactured using open cavity molding processes typically have one smooth side, formed from the top surface of the material in the mold, and one featured side having a number of contoured features formed therein by contours in the bottom surface of the concave portion of the mold. For typical floor mats manufactured using the prior art processes described above, the bottom surface of the floor mat is substantially smooth, and the top surface has a number of contours or features that provide a textured surface.
For floor mats and other products, it is sometimes desirable to have features formed on the top and bottom surfaces of the products, and to provide products having multiple colors. While it is possible to produce such products using processes other than open cavity molding, such as injection molding, these other processes are typically more complex and therefore more expensive than open cavity molding. It is also sometimes desirable to incorporate fabric into a portion of the top surface of the product to provide, for example a carpeted section of a floor mat.